Yarn of reduced liveliness and pile carpet thereof



Oct. 7, 1969 3 NEW ET AL 3,470,836

YARN OF REDUCED LIVELINESS AND FILE CARPET THEREOF Filed Sept. 26, 1967 INVENTORS H Y E. NEW D R. GREEN BY i ATTORNEYS United States Patent 3,470,836 YARN 0F REDUCED LIVELINESS AND PILE CARPET THEREOF Harry E. New and Dick R. Green, Newport News, Va.,

assignors to The Dow Chemical Company, Midland, Mich., a corporation of Delaware Filed Sept. 26, 1967, Ser. No. 670,680

Int. Cl. Db 35/00; D02g 1/02, 3/00 U.S. Cl. 112-410 7 Claims ABSTRACT OF THE DISCLOSURE DISCLOSURE This invention relates to yarns of reduced liveliness and to pile carpets incorporating these yarns.

Yarns suitable for the manufacture of woven fabrics, knit goods, and pile fabrics are produced by procedures well-known in the art. By these procedures filaments are twisted into strands, a plurality of which are then twisted into yarns. These two twisting operations impart to the resultant yarn an amount of latent energy which manifests itself in the tendency of the yarn to twist. This tendency is known as yarn liveliness or yarn torque. While this yarn liveliness is acceptable or even desirable in certain applications, it creates a number of difficulties during the subsequent manufacture of textile goods from these yarns, and imparts certain undesirable characteristics to these textile goods. In particular it causes kinking of the yarn during the weaving of woven textiles. This kinking causes an undesirable uneven surface effect. Knit fabrics produced of lively yarns exhibit an undesirable skew..

Particularly troublesome problems occur during the manufacture of pile carpets. The liveliness of the yarn causes difficulty in tufting due to inter-twining of the strands in the creel, the inability to form positive loops, and the tendency for formed loops to curl back into subsequent stitches thus causing sew-through of the loops. Pile carpets produced from these lively yarns exhibit a number of undesirable effects. The liveliness of the yarn causes certain of the loops to twist upon themselves. Since this effect does not occur uniformly the surface of the pile fabric exhibits a streaked appearance. This streaked appearance has been minimized in the past by employing pile loops of slightly different heights in order to mask the streaked eifect. Additionally the liveliness of the yarn in the loops causes twisting of the loops which reduces the initial height of the loops. In order to compensate for this reduction in height of the loops it is necessary to employ longer loops requiring a greater amount of yarn with a consequent increase in the cost of the pile fabric. Furthermore pile fabrics employing loops of lively yarns are not resilient in that once stepped upon the loops do not readily return to their original height. This causes undesirable matting of the pile fabric. Furthermore the difference inheight of the pile under light foot pressure and full foot pressure is relatively small and does not impart a luxurious feel to these pile fabrics when used as carpets.

It is therefore an object of the present invention to provide a novel method for reducing the liveliness of yarns.

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Another object of the present invention isto provide a novel yarn of reduced liveliness.

A further object of the present invention is to provide a pile fabric of increased pile resilience, and especially a pile fabric useful as a carpet.

A still further object of the present invention is to provide a novel pile carpet having pile loops of uniform height and presenting a uniform appearance.

Yet another object of the present invention is to provide a novel pile carpet having a luxurious feel.

Still another object of the present invention is to provide a novel pile carpet employing yarns of reduced liveliness.

Still another object of the present invention is to provide a pile carpet having a greater initial thickness than heretofore possible and having pile loops of the same height.

Additional objects and advantages of the present invention will be apparent by reference to the following detailed description thereof.

The above and other objects are accomplished by providing a yarn of reduced liveliness comprising at least two twisted strands. The first strand is twisted a different amount in the same direction as the second twisted strand. When pile loops of these yarns are anchored in a backing material with portions extending above the backing material the result is a resilient pile carpet possessing the above described and other advantages. Although the present invention is primarily applicable to pile fabrics having continuous loops it is also applicable to pile fabrics having cut loops.

The invention may be better understood by reference to the following detailed description thereof and the accompanying drawings wherein:

FIGURE 1 shows a two ply yarn of the present invention and,

FIGURE 2 shows a three ply yarn of the present invention and,

FIGURE 3 is a warp wise cross section showing (1) a pile fabric of the present invention employing yarns of the present invention, (2) a method of construction of such a pile fabric and (3) a method of testing such a pile fabric.

Referring now to the drawings and in particular to FIGURE 1 thereof, there is shown a yarn 10 of the present invention. The yarn 10 comprises a first twisted strand 11 and a second twitsed strand 12 and is thus a two ply yarn. Both the strand 11 and the strand 12 are constructed of a plurality of filaments 13. In accordance with the present invention the first strand 11 is provided with five turns per inch of twist in the Z direction and the second strand 12 is provided with three turns per inch in the Z direction. The first strand 11 and the second strand 12 are plied into the yarn 10 with 4.0 turns in the S direction.

Referring now to FIGURE 2 there is shown another yarn 20 of the present invention. This yarn 20 comprises three strands, a first strand 21, a second strand 22, comprised of filaments 23 as described above for the yarn 10, and a third strand 24. The first strand 21 is provided with three turns per inch Z, the second strand 22 is provided with four turns per inch Z, and the third strand 24 is provided with five turns per inch Z. The three strands 21, 22 and 24 are plied into the three ply yarn 20 with 2.80 turns per inch S.

' Referring now to FIGURE 3, there is shown a pile carpet 30 of the present invention employing the yarn 10 of FIGURE 1. The pile carpet 30 comprises abacking material 31 and a plurality of pile loops 32. The pile loops 32 are anchored in the backing material 31 and have portions extending above the backing material 31. The pile carpet 30 can be constructed by passing a needle 3 33 which has been threaded wtih the yarn 10, through the backing material 31 as shown.

The thickness of the pile carpet 30 can be measured under varying pressures by placing the pile carpet 30 on the fiat upper surface 34 of any convenient support 35, and then placing a flat plate 36 having a lower surface 37 on the top of the pile loops 32 of the pile carpet 30. Varying pressures can then be exerted on the plate 36 in the direction of the arrow 38 and the thickness, 2, measured under these load conditions by determining the distance between the surface 34 and the surface 37. From these measurements a number of parameters can be calculated.

. The pile fabrics of the present invention can have their pile loops sewed to the surface of the backing material or can have the pile loops incorporated into the backing material during the weaving operation. However the pile carpets of the present invention are preferably constructed by pushing the yarn of the present invention through the backing material as described above and is well-known in the art. Suitable methods for constructing the pile fabrics of the present invention are disclosed in U.S. Patents 2,448,928 and 2,810,948.

The yarns of the present invention consist of a plurality of strands and while any convenient number of strands can be employed yarns having two, three or four strands are preferred. While the strands of the yarns can run parallel to one another, they are preferably plied into the yarn in a twist having a direction different than that of the twist of the strands themselves. Thus for example, when the strands have a Z twist they are incorporated into the yarn with an S twist and vice versa.

At least two strands in each yarn must have a diiferent amount of twist i.e. the number of turns per inch in one yarn must be different than that of at least one other yarn. This difference is preferably between 0.5 and 3.0 turns per linear inch. Thus for example when the first strand has a twist of three turns per inch at least one other strand in the yarn'will have a twist of from to 2.5 or from 3.5 to 6 turns per linear inch. In a preferred embodiment of the present invention the yarn has three strands all twisted a different amount in the same direction. A particularly preferred embodiment of the present invention is a yarn having two strands the first of which is twisted five turns per inch in the Z direction the second strand of which is twisted three turns per inch in the Z direction, the first and second strands being plied into a yarn with four turns per inch in the S direction.

The yarns of the present invention can be produced on conventional spinning and twisting machines. These machines are generally equipped with a drive motor coupled to twisting apparatus via reduction gears. By the selection of these gears it is possible to give an exact twist per inch to the strands and to the yarn. Selection of appropriate gear ratios and modifications of existing machines to produce the yarns of the present invention is well within the skill of the art.

The filaments which can be employed to construct the strands useful in producing the yarns of the present invention can be any of those previously employed for similar purposes. Thus the filaments can be of naturally occurring fibers or synthetics. Examples of suitable naturally occurring fibers include among others wool, cotton and hemp. Examples of suitable synthetic filaments are those of rayon, nylon, polyethylene terephthalate, and the acrylic fibers such as polymerized iacrylonitrile which can be homopolymerized or copolymerized with other vinyl monomers as is well-known in the art. The filaments can be employed in the form of tows of continuous filaments or can be cut into staple and then spun.

The backing materials useful to produce the pile carpets of the present invention can be any backing material previously employed for similar purposes, examples of which include among others the woven and non-woven backing materials of fibers such as jute or hemp. The carpets of the present invention and especially the backing material thereof can be treated with known treating agents such as size, latex, flame retardant agents, antislip agents and the like.

The invention may be better understood by reference to the following examples which are illustrative of certain embodiments of the present invention designed to teach those skilled in the art how to practice the invention and to represent the best mode contemplated for carrying out the invention and are not intended to limit the scope of the invention in any manner. Certain control examples are given for purposes of comparison.

Example 1 This example illustrates the production of certain yarns of the present invention as well as a control yarn.

A standard 1.10 count woolen run strand is produced from a blend of 70 weight percent of 15 denier, 4 inch long staple of polymerized acrylonitrile and 30 weight percent of 16 denier, 4 inch long modacrylic staple, sold by the Eastman Kodak Company under the trade name Verel. The resultant strand has a denier of 2530. These strands are then incorporated into various yarns as follows. Yarn A is produced by giving one of the above strands 4 turns per inch Z and a second of the above strands, 3 turns per inch Z. These two strands are then plied with 3.5 turns S to yield a yarn of the present invention termed Yarn A. Yarn B is produced by giving one of the above strands 5 turns per inch Z, a second of the above strands 4 turns per inch Z and plying these two strands with 4.5 turns per inch S. Yarn C, a yarn of the present invention is produced by giving one of the above strands, 5 turns per inch Z, a second of the above strands, 3 turns per inch Z, and plying these two strands with 4.0 turns per inch S. A control yarn not illustrative of the present invention, termed Yarn D, is produced by giving one of the above described strands 4 turns per inch Z, giving the second of the above described strands 4 turns per inch Z and plying these two yarns with 3.5 turns per inch S.

Example 2 This example illustrates the construction of a pile carpet of the present invention.

Yarns A, B, C, and D are each separately tufted into a jute backing material on a single needle loop pile tufting machine, adjusted to give 30 ounces per square yard of the yarn on the backing material. These four carpet samples are tested as described below and the results of these tests recorded in Table I.

One square yard of the carpet is weighed and from this weight is subtracted the weight of one square yard of the backing material. The actual amount of yarn per unit carpet area is then recorded in column 2. Each of the carpet samples is placed on a support, similar to the support 35 of FIGURE 3. A plate 36 is then placed on the pile loops 32 of the carpet with a compressive force of 0.1 p.s.i. The distance, z between the upper surface 34 of the support 35 and the lower surface 38 of the plate 36 is recorded in column 3a of TableI. The pressure on the plate 36 is increased to 1.0 p.s.i. and the corresponding figure t recorded in column 3b of Table I. The force on the plate 36 is further increased to 2.0 p.s.i. and the dimension t is recorded in column 3c of Table I. The force on the plate 36 is further increased to 9.0 p.s.i. and the dimension t recorded in column 3d of Table I. The pressure on the plate 36 is then decreased to 2.0 p.s.i. and the dimension t measured and recorded in column 3e of Table I. The value in column 3c is less than the value in column 30, since the pile loops 32 do not regain all of their original height.

Employing the data recorded in columns 3a through 3e inclusive, certain other parameters of the pile fabrics of the present invention and the control pile fabric employing Yarn D are calculated. These parameters are re- 5 corded in columns 4, 5 and 6 of Table I. The height of compression is computed by subtracting r from t This value is also termed the luxury factor and is proportional to the distance by which one walking on the carpet sinks into the carpet. The greater the height of compression,

6 Example 4 This example illustrates the production of yarns of the present invention employing nylon. This example also illustrates the construction of carpets of yarns of the present invention and the difliculties encountered employing the more luxurious the feel of the carpet. Pile carpets hav- 5 control yarns. mg a large height of compresslon give a very luxurious This exam 1e em 10 s Strands f I h 204 fil feel and find wide consumer acceptance. As can be seen p p y o my on avmg ments per strand and a denier of 3700. Yarn G, a control by reference to column 4 of Table I, the plle carpets of yarn 1s produced by plying two of the above strands with the present mventron exhibit a greater height of compresthree turns S Zero twist is a d to th t a d Y H sion than the control carpet employing control Yarn D. 10 a am of resent g gg 2 The percent recovery which is recorded in column 5 y p 1 P u y lmpar mg to one strand three turns per mch Z and to the other strand of Table I 1s the percent difference 1n the measurement of t h Z Th d the He hei ht at 2 di th 60 r a d urns per nc ese two stran s are thenpred W1 p g p.s.1. a n e mp es 10a 11 re 3 turns per inch S. Yarn J 1s produced by imparting to one covery curve obtamed by compresslon to 9 p.s.1., which 15 strand one turn per 1nch Z and to the second strand 2 thickness measurements are corected by subtracting the turns per inch Z and 1 in the two Strands with two turns thickness at 9 p.s.i., and is equal to: per inch S p y g 100 (te d) The liveliness of Yarn G was so great that it is neces- (tc td) sary to hold the yarn to prevent excessive kinking during 0 the single needle loop pile tufting. The carpet produced The most desirable situation would be to have t equal f o Y G exhibited a very uneven pile height, and to o 111 whleh'case the P n recovery would be 100, had a very soft hand, although it did have greater cover f the higher the pel'eellt recovery the Inole P Y than the pile carpets produced from Yarns H and 1. Caris the pile carpet. The percent recovery 1s only one parampets produced from Yarns H and I have a firmer hand eter of measurmg carpet performance and has been found h carpets d d from Y G h carpet employhe y effected y the amount of y the Carpet ing Yarn H being the firmest and having the least cover. pile as recorded in column 2 of Table I. The liveliness of Yarns H and I gave no problem in tuft- The product of the nk height, column 4, and percent ing and the pile carpets produced therefrom exhibited a recovery, column 5, gives a value called recovery 1ndeX, uniform pile height, and showed no streaks. recorded in column 6, which has been found to more What is claimed is: nearly Correlate with the carpet Performance during actual 1. A yarn of reduced liveliness comprising at least a wear testing. As can be seen by reference to column 6 first twisted strand and a second twisted strand wherein the pile carpet employmg Yarn B and that employing said second twisted strand is twisted a diiferent amount in Yarn D have essentlally the same recovery index, wherethe same direction as said first twisted strand, and whereas the recovery lndlces of he pile carpets employing in the two strands are plied into the yarn by twist in a di- Yarns Aand C show significant lmprovement. rection opposite to the twists of the strands.

The pile carpets employmg Yarns A, B and C are uni- 2. The yarn of claim 1 wherein the difference in twist form and even in appearance whereas that employing between said first twisted strand and said second twisted Yarn D exhibits undesirable streaks. strand is between 0.5 and 3.0 turns per linear inch.

TABLE I Thickness under compression a b c d e Compres- Recovery sion at 2.0 index Amount of p.s.i. after (value in yarn per Compres- Compres- Compres- Comprescompres- Height of Percent column 4 unit carpet sion at 0.1 sion at 1.0 sion at 2.0 sion at 9.0 sion at 9.0 compression recovery, times Designation of yarn area p.s.1. a) p.s.i. (ts) p.s.i. (ts) p.s.i. (ta) p.s.i. (ta (tn-t4) loom-ts) value in in the carpet (on/yd (inch) (inch) (inch) (inch) (inch) (inch) (t -ta) column 5) 29.8 .463 .370 .319 .195 .238 .268 34.7 9.30 so. a 435 331 283 180 .215 255 34. 0 8.67 30. 4 .443 .341 2ss 183 .221 260 as. 2 s. 41 31. 7 41s s43 301 .200 242 .213 40. 6 s. 65

Example 3 3. The yarn of claim 1 further comprising a third This example illustrates yarns of the present invention constructed of three strands, and cut pile fabrics of the present invention.

The strands of Example 1 are twisted into yarns as follows. Yarn B is constructed by twisting three strands, the first strand being given 3 turns per inch Z, the second strand being given 4 turns per inch Z, and the third strand being given 5 turns per inch Z. These three strands are then plied into a yarn termed Yarn E with 2.80 turns per inch S. A control yarn termed Yarn F is constructed by twisting three strands each three turns per inch Zand plying them into a yarn with 2.80 turns per inch S.

Yarns E and Fare each tufted into a backing material as described in Example 2. A portion of the pile loops on each sample are cut. The pile carpet employing Yarn B exhibits the same improved characteristics as the pile carpets in Example 2 employing Yarns A, B and C. The cut pile carpets employing-Yarn E hold the twist in the cut loops better than did the carpet employing Yarn F.

strand which is:

' (1) twisted in the same direction as said first and second strands,

(2) twisted a difierent amount than said first strand and (3) twisted a different amount than said second strand.

4. The yarn of claim 1 wherein the first strand is twisted 5 turns per inch Z, the second strand is twisted 3 turns per inch Z, and the first and second strands are plied into a yarn with four turns per inch S.

5. A resilient pile carpet comprising a backing material and pile loops of the yarn of claim 1 anchored in said backing material, having portions extending above said backing material.

6. The pile carpet of claim 5 wherein said backing material is a woven fabric and wherein said pile loops pass through the backing material and are thereby anchored in the backing material.

7. A resilient pile carpet presenting an even appearance, said carpet comprising a backing material and a plurality of pile loops of the yarn of claim 1, said loops being anchored in said backing material and extending an even distance above said backing material.

References Cited UNITED 3,011,243 12/1961 Herrnstadt '57139XR v FOREIGN PATEN'lS 5 713,072 8/1954 Great Britain STATES PATENTS STANLEY N. GILREATH, Primary Examiner Bouvet et a1 57140 Sultan 57 14o WERN Af Geier et a1. 57-140 10 U.s.c1.x.1i.

Jackson s7- 139 XR 57 -139, 140 

